1. Field of the Invention
The present invention relates to a still picture recording and reproducing apparatus having an edit function and capable of recording a still picture of a plurality of record formats.
2. Description of the Prior Art
FIG. 1 is a block diagram showing an example of a still picture recording and reproducing apparatus having an edit function in the prior art. In FIG. 1, A, B designate two still picture recording and reproducing apparatuses used for editing respectively, numeral 101 designates a recording and reproducing apparatus containing a record medium for performing recording and reproducing, numeral 109 designates a frame memory for image display, numeral 107 designates a D/A converter for converting data read out from the frame memory 109 for image display into analog data, and numeral 108 designates a frame memory for communication with the frame memory 109 for image display.
In the following description, the still picture recording and reproducing apparatus A, B will be simply called apparatus A and apparatus B.
In the prior art, editing of a still picture has been carried out using two or more still picture recording and reproducing apparatuses. Here, operation in the case of editing a still picture of the apparatus A by the apparatus B will be explained. First, data recorded in the record medium of the recording and reproducing apparatus 101 of the apparatus A are reproduced. The data are written in the frame memory 108 for communication of the apparatus A in synchronization with the reproducing clock. After finishing writing, the data are read out from the frame memory 108 for communication in synchronization with the clock for image display and written in the frame memory 109 for image display of the apparatus A. After finishing the data transfer, the data pass through the D/A converter 107 of the apparatus A and are outputted as analog signal and displayed as an image. Here, when the displayed image is not recorded in the recording medium of apparatus B, apparatus A continues to reproduce according to the above-mentioned procedure until the image desired to be recorded appears.
When the still picture displayed in apparatus A is to be recorded in the recording medium of apparatus B, data of the frame memory 108 for communication by apparatus A are read out in synchronization with clock in recording operation to the recording medium of apparatus B and are recorded in the recording medium of apparatus B. Thus editing becomes possible in that any still picture is selected from the recording medium of apparatus A and recorded in the recording medium of apparatus B.
When the still picture is edited using the still picture recording and reproducing apparatus in the prior art in this manner, the two similar apparatuses A and B are required and moreover the operability is poor.
Also in the prior art, since characters such as date, title or the like is superimposed on the image and recorded as a part of the image to the recording medium, it is difficult for the character once recorded to be subsequently changed.
FIG. 2 is a block diagram showing a still picture recording and reproducing apparatus in the prior art. In FIG. 2, numeral 201 designates a comb filter for carrying out Y-C separation of a composite signal, numeral 202 designates a decoder for producing color difference signals of R-Y, B-Y from the signals of Y, C, numeral 203 designates a signal changing circuit for selecting one recording format among Y, R-Y, B-Y signals produced from a monochromatic signal and a composite signal as well as RGB signals, numeral 214 designates an A/D converter for converting an input signal selected in the signal changing circuit 203 from analog into digital, numeral 212 designates a frame memory for storing a signal subjected to digital conversion, numeral 210 designates a recording and reproducing apparatus that data, read out from the frame memory 212 are recorded and reproduced in a recording medium such as a magnetic tape, numeral 213 designates a frame memory for storing a reproducing signal of the recording and reproducing apparatus 210, and numeral 215 designates a D/A converter for converting data read out from the frame memory 213 into analog data.
Numeral 205 designates a signal changing circuit for selecting in which record formatting among a monochromatic signal, and a color difference signal, RGB signals should be used for data sent from the D/A converter and for sending the data to the next stage, numeral 206 designates an encoder for producing a composite signal from color difference signals of Y, R-Y, B-Y selected in the signal changing circuit 205, numeral 207 designates a signal changing circuit for selecting one among composite and monochromatic input signals and a reproduced monochromatic signal and a reproduced composite signal and for outputting the selected signal, numeral 208 designates a signal changing circuit for selecting one among the RGB input signals and the reproduced RGB signals and for outputting the selected signal, numeral 211 designates a recording format selecting circuit, and numeral 209 designates a microcomputer for reading information of a selected recording format and for controlling and changing the signal changing circuits 203, 205, 207, 208 in response to the information.
FIG. 3 is a flow chart showing operation in a recording state, and FIG. 4 is a flow chart showing operation in a reproducing state.
First, operation in a recording state will be described referring to FIGS. 2 and 3. In step ST301, information of a recording format selected by a switch within the recording format selecting circuit 211 is sent to the microcomputer 209, and in response to the information, the signal changing circuit 203 is changed in step ST302. If recording is started in step ST303, when the input signal is a monochromatic signal, the input signal is written through the signal changing circuit 203 and the A/D converter 214 into the frame memory 212, and after finishing the writing, the data are read out and recorded in a tape by the recording and reproducing apparatus 210. When the input signal is a composite signal, the input signal is written through the comb filter 201, the decoder 202, the signal changing circuit 203 and the A/D converter 214 into the frame memory 212 and then the data are recorded on a tape in similar operation to that of the monochromatic signal as above described. When the input signal is of RGB type, the input signal is written through the signal changing circuit 203 and the A/D converter 214 into the frame memory 212 and then the data are recorded in a tape in similar operation to that of the composite signal. When image data of a still picture are recorded, if the number of sheets of the image capable of being recorded in one record medium is made constant, as this is convenient for use and the control becomes easy, the record capacity per each image is made constant. In step ST304, the recording is finished. During the recording operation, the input signal is output exactly and monitored by the signal changing circuits 207, 208.
Next, operation in the reproducing state will be described referring to FIGS. 2 and 4. First, before reproducing, in step ST401, a switch within the recording format selecting circuit 211 is set by a user in order to indicate the recording format in the recorded tape. The information is sent to the microcomputer 209 in step ST402, and in response to the information, the signal changing circuits 205, 207, 208 are changed. If reproducing is started in step ST403, data are reproduced from the recording and reproducing apparatus 210 and the reproduced data are output in step ST404.
In the case of a monochromatic signal, data reproduced from the recording and reproducing apparatus 210 are written in the frame memory 213, and after finishing the writing, the data are read out from the frame memory 213 and subjected to analog conversion by the D/A converter 215 and output through the signal changing circuits 205, 207. When the record format is a composite signal format, operation to the D/A converter 215 is similar to that in the case of the monochromatic signal as above described, and then data pass through the signal changing circuit 205 and a color difference signal is encoded to a composite signal by the encoder 206 and output through the signal changing circuit 207. When the record format is RGB signal format, operation to the signal changing circuit 205 is similar to that in the case of the monochromatic signal and the composite signal as above described, and then data are output through the signal changing circuit 208.
In general, the image data amount is significantly different in monochromatic, composite, RGB signals respectively. In the prior art, however, since the function of individually setting recording capacity per one picture plane in response to the recording format is not provided, the recording capacity must be fitted to the maximum image data amount in the recording format and therefore the record medium cannot be utilized effectively. Since the recording operation is carried out also in the case of the input signal, erroneous recording may occur. For example, when a signal is input to RGB to RGB signals and the recording format is set to a composite signal format, since the composite input has no signal, if the recording is carried out, the recording in composite having no signal will be carried out. Since an input signal appears intact at the output during the recording, even if only output of each signal is seen, the setting mistake of the recording format is not noticed, and the erroneous recording is not noticed before reproducing. During reproducing, since the setting of the recording format must be varied in response to the recording medium, the work is troublesome and if the setting mistake occurs, an abnormal image will be output. For example, if data of color difference with a composite signal decoded are output as RGB signals, the color will become quite abnormal.
FIG. 5 is a block diagram showing an example of a still picture dubbing apparatus in the prior art. In FIG. 5, numeral 561 designates an A/D converter for converting data of the green image (still picture or movie picture) from analog into digital, numerals 562, 563 designate A/D converters for red, blue respectively, numeral 564 designates a D/A converter for converting data of the green image from digital into analog, numerals 565, 566 designate D/A converters for red, blue respectively, numeral 567 designates a frame memory for exclusive display of still picture in green, numerals 568, 569 designate frame memories for display of red and blue still pictures and movie pictures respectively, numeral 570 designates a frame memory for communication between the frame memory 567 and a recording apparatus 585 described later, numerals 571, 572 designate frame memories for communication between the frame memories 568, 569 and the recording apparatus 585 respectively, numeral 587 designates a three-state input buffer for buffering green image data during dubbing, and numerals 589, 591 designate three-state input buffers for buffering red and blue image data respectively during dubbing.
Numeral 588 designates a three-state output buffer for buffering green image data during dubbing, numerals 590, 592 designate three-state output buffers for buffering red and blue image data respectively during dubbing, numeral 580 designates a three-state buffer which is enabled when image data are written from the recording apparatus 585 into the frame memory 570, numeral 582 designates a three-state buffer which is enabled when image data are written into the frame memory 571, and numeral 584 designates a three-state buffer becoming enable when image data are written into the frame memory 572 respectively. Numeral 573 designates a three-state buffer which is enabled when image data are written from the frame memory 570 into the frame memory 567, numeral 575 designates a three-state buffer which is enabled when image data are written from the frame memory 571 into the frame memory 568, and numeral 577 designates a three-state buffer which is enabled when image data are written from the frame memory 572 into the frame memory 569 respectively. Numeral 585 designates a recording apparatus for recording images.
Data Transmission During Dubbing
In FIG. 5, image data recorded in the recording apparatus 585 are reproduced in the order of green, red, blue, and pass through three-state buffers 580, 582, 584 respectively, and are stored in the frame memories 570, 571, 572 in synchronization with a read clock of the recording apparatus 585. Afterwards image data stored respectively in the frame memories 570, 571, 572 are read out, and pass through the three-state buffers 573, 575, 577 and are transferred to the frame memories for image display 567, 568, 569 in synchronization with image display clock. Image data stored respectively in the frame memories 567, 568, 569 are read out and converted into analog data by the D/A converters 564, 565, 566. Thus color images are reproduced and displayed in a display apparatus (not shown) connected to these D/A converters.
Here, the same data as the image data for image display transferred from the frame memories 567, 568, 569 to the D/A converters 564, 565, 566, pass through three-state buffers 588, 590, 592 and are transmitted for dubbing to a destination apparatus (not shown).
Then outputs of the three-state buffers 579, 581, 583; 574, 576, 578; 587, 589, 591 have high impedance.
Data Reception During Dubbing
During reception, first, image data for dubbing are sent from the destination apparatus, and the green image data pass through the three-state buffer 587, the red image data pass through the three-state buffer 589, the blue image data pass through the three-state buffer 591 respectively, and then the image data are stored in the frame memories 567, 568, 569 respectively. The image data stored respectively in the frame memories 567, 568, 569 are read out, and then pass through the three-state buffers 574, 576, 578 respectively and are transferred to the frame memories 570, 571, 572 in synchronization with image display clock. Afterwards image data stored respectively in the frame memories 570, 571, 572 are read out, and then pass through the three-state buffers 579, 581, 583 and are sent to the recording apparatus 585. The recording apparatus 585 takes image data from the three-state buffers 579, 581, 583 in synchronization with write clock of the recording apparatus 585 and records the color images in the record medium. Then outputs of the three-state buffers 588, 590, 592; 593, 575, 577; 580, 582, 584 have high impedance.
As similar technology, JPA No. 159191/1990 discloses technology that video signals are stored in a semiconductor memory, and the stored video data are transferred through a system bus. Also JPA No. 220580/1990 discloses technology that in a storing and reproducing apparatus of still picture, data are stored in two data rates and then read out in two data rates.
In a still picture dubbing apparatus in the prior art, a data rate (transfer speed) during dubbing is the same as that of image display and therefore becomes very high speed. At present, sampling clock of image display of composite and RGB is about 15 MHz, and at speed in response to this clock, data are transferred also at high speed. As a result, since the influence to of crosstalk of other signal lines, unnecessary radiation, timing relation between data and clock, attenuation of signal respectively is large, this must be considered.
Also since transmission and reception are carried out using data for image display, horizontal synchronous signal and vertical synchronous signal are transmitted and received at the same data rate as that of image display. Since horizontal synchronous signal and vertical synchronous signal are always the same in any image, dubbing is not necessary. Further at image display interval other than horizontal and vertical synchronous signals, in general, several regions at both ends of the screen actually displayed are not used.
Also in dubbing, many dubbing terminals are required, in order that data of each image of RGB are simultaneously transmitted and received. Thereby various problems occur in that the connector for dubbing becomes large, and the space efficiency is deteriorated or convenience of use is poor. Also a dubbing operation due to connection failure or no connection of the connector cable accompanying with this may cause a problem that erroneous recording occurs frequently.